If this book doesn't have you talking in a fake Scottish accent every time you pick it up, then you can probably ignore all of Terry Pratchett's books. This has the kind of clever silliness that could rub you the wrong way if you're not in the mood for it or prefer your sci-fi books to be more clever than silly.
So, this little frolic is about a girl who wonders if she is a witch, has had her brother taken by an evil fairy queen, and is beset by these odd little blue men (those of the Scottish accents) who attempt to help her defeat the queen and get her brother back. See what I mean? I can't even begin to imagine how awful this type of tale would be in a lesser writer's hands. Even though I'm not a writer, I know this much: building a fantasy world and populating it with characters we have empathy for might be a difficult task in and of itself, but making it *believable*? That is the trick.
And funny! Once in a blue moon, I'll hear my husband laugh while reading a novel. This one made him giggle. A lot. Laugh out loud moments are aplenty, and as you might guess, those wee men are the ones making that happen. In fact, the girl herself is a deadly serious, too-smart-for-her-own-good type of girl. We empathize with her, but she's going to a damn formidable woman, you can see that right away.
My only quibble with the book is its length. By that I mean, that there are several twisty plot bits towards the end that seemed about thrice as many as necessary. One really excellent, slightly lengthier twisty bit would have served the book better. I got a bit tired of waiting for the true end.